基本信息
摘要：995, 252. Liquid level control and indication. HALKERGERHUTTE G.m.b.H. Dec. 21, 1961 [Dec. 24, 1960], No. 45887/61. Heading G1H. [Also in Division G4] A liquid level indicating and/or controlling device comprises a transparent gauge tube 1 connected to the container and containing a float 2 of opaque material when the liquid is transparent and of transparent material when the liquid is opaque and two housings 3,4 at opposite sides of the tube respectively containing a semi-conductor photosensitive means 5 and a convex lens 8 which brings light rays 9 to a focus on the means 5. The photosensitive means may be a germanium photo-diode or a silicon photo-cell. In operation the opaque float interrupts the light rays or, in the case of a transparent float, allows them to pass, when it reaches the level of the housings whereby in each case the means 5 transmits an electrical pulse to an amplifying relay. Housings can be located at desired high and low levels and the relay arranged to stop or start a filling pump and to operate acoustic or visual signals. A number of housings may be arranged on the gauge tube so that switching operations for control and/ or indication may occur at selected levels. The housings may be provided with cooling fins.
摘要附图：
